The present invention relates to a method of filling liquid into a cartridge of a liquid jet apparatus such as a printer, display manufacturing device, electrode forming device, or biochip manufacturing device having a liquid jet head that jets liquid droplets through openings of nozzles. The present invention also relates to a liquid filling device, and a cartridge.
Even though a liquid jet apparatus having a liquid jet head that jets liquid droplets through openings of nozzles jets various kinds of liquid, what is most widely known is a recording head mounted on an ink jet recording device. Therefore, the ink jet recording device will be used as an example for the description.
The ink jet recording device includes a liquid jet head that ejects liquid, such as ink, and records images such as letters, figures or the like; and a cartridge that stores the liquid, such as ink, which is to be supplied to the liquid jet head, and, in general, the cartridge can be detached from the ink jet recording device for replacement. When the ink in the cartridge is used up, and thus images cannot be recorded, images can be recorded again by replacing the used cartridge storing no ink with a brand-new cartridge storing ink.
In recent years, it has been sought that the used cartridge is injected with ink for recycling, since serious problems such as increase of waste and environmental load occur when the used cartridge is disposed after a single-time usage.
In order to reuse the used cartridge, there is proposed a refilling method of the ink cartridge of the ink jet recording device, in which ink remaining in an ink bag is discharged and a specified amount of ink is injected into the ink bag (for example, see Patent Document 1). In the method disclosed in Patent Document 1, the ink bag is pressed by a pressing plate in a low-pressure chamber in order to discharge the ink remaining in the ink bag, and then the specified amount of ink is injected into the ink bag.
In addition, there is proposed a method of ink replenishment, through which ink is replenished into the used cartridge storing no ink (see Patent Document 2). In the method disclosed in Patent Document 2, ink is replenished by a replenishing unit while a suction unit is sucking the ink in an ink tank.
Patent Document 1: Japanese Patent Laid-Open No. 10-193635
Patent Document 2: Japanese Patent Laid-Open No. 11-207990
However, in the method disclosed in Patent Document 1, the specified amount of ink is injected into the ink bag while the ink bag is pressed by the pressing plate in the low-pressure chamber and thus the ink remaining in the ink bag is discharged. Therefore, the method cannot be applied to a hard case cartridge having a fixed shape. In addition, since the ink is discharged from the ink bag by a device having a vertically movable pressing plate in the low-pressure chamber, the configuration of the device and the process become complicated. As a result, the recycling cost increases.
In addition, in the method disclosed in Patent Document 2, since ink is replenished while the ink in the cartridge (ink tank) is being sucked, the degassed rate of the cartridge can be decreased, or a great amount of deteriorated ink can remain in the ink bag due to the increased viscosity thereof (the viscosity is increased by drying) so as to be mixed with the replenished ink, or the replenished ink can contain many air bubbles, and thereby it is highly likely that the ink cannot ensure a required quality when reused. In contrast, when it is sought that the remaining ink is discharged completely, it is likely that the replenished ink can be mixed with the remaining ink then discharged, and thereby the amount of replenished ink can be decreased. That is, it is difficult to ensure the quality and yield of the ink of the recycled cartridge at the same time, and thereby the both methods are not satisfactory. Furthermore, since ink is injected from a supplying opening that supplies ink into a printer or the like and then held in an ink holding member in the cartridge, the ink flowing direction during suction or injection is opposite to the ink flowing direction during using, and the ink bubbles so as to remain in the form of air bubbles in the cartridge. As a result, it is likely to cause the inferior jetting of the jet head while the recycled cartridge is being used.
As described above, Patent Documents 1 and 2 never mention how to ensure the yield of the cartridge by sealing the ink-refilled recycled cartridge reliably, much less study about the above matter.
Further, Patent Documents 1 and 2 never mention how to remove the air bubbles in a recycled cartridge and how to prevent the inferior jetting of the liquid jet head when the recycled cartridge is used, much less study about the above matters.